This invention relates to the production of joints between metallic and plastic components and, more particularly, to a new and improved joint and process for producing such a joint.
In many applications, hollow, i.e., tubular, torsion-stressable shafts of fiber-plastic compound materials containing glass or carbon fibers are utilized for reasons of weight and noise reduction, for example, in the torque transmission between a driving unit, on the one hand, and a differential gear unit, on the other hand, of an automobile. The construction of the joint between the ends of such a torsion tube and adjacent couplings, such as constant-velocity couplings, having components which are made of rigid material such as metal, is difficult. Attempts to join such plastic and metal components with cement have not been very promising, in spite of extensive efforts. The provision of clamping sleeves on the retaining region of such a torsion tube poses problems of extra expenditures of material and labor, at least in large-scale manufacture, such as in the automobile industry.
In German Patent No. 27 28 306, a rigid connection between a fiber-reinforced synthetic resin shaft and a coaxial metallic drive component, such as a component of a constant velocity coupling, has an inner sleeve with a knurled outer surface on which the resin shaft is mounted, the inner sleeve being subsequently joined to the coupling proper by welding. In this case, the bond between the inner sleeve and the shaft is achieved by a hardening heat treatment. As a result of this treatment, the resin is bonded to the inner sleeve. This method, which uses a knurled outer surface on the inner sleeve, requires a relatively complex fabrication procedure.